[URL="http://api.tweetmeme.com/share?url=http://espn.go.com/nfl/story/_/id/6802383/aj-smith-san-diego-chargers-treads-lightly-vincent-jackson-future?campaign=rss&source=NFLHeadlines&service=bit.ly&source=espn"][IMG]http://api.tweetmeme.com/imagebutton.gif?url=http://espn.go.com/nfl/story/_/id/6802383/aj-smith-san-diego-chargers-treads-lightly-vincent-jackson-future?campaign=rss&source=NFLHeadlines[/IMG][/URL]Vincent Jackson's long-term future in San Diego is uncertain -- that much is for sure.